The present invention relates to projection devices and, more particularly, to an apparatus and method for projection upon a three-dimensional object.
The projection of an image onto a three-dimensional object having various contours and shapes is not an easy task. It is generally known that the correction of all optical distortion problems inherent in flat, two-dimensional image projection is especially difficult when working with three-dimensional projection surfaces. These problems include proper image registration on the object, proper keystoning, corrections to ensure appropriate perspective appearances and focusing of the image within a specified range of depth.
Through the years, various attempts have been made to project images onto three-dimensional objects. For example, from the days of early artists it has been known to transfer three-dimensional images to two-dimensional images by using a pane of glass and tracing the three-dimensional image by eye onto the glass. In general, these three-dimensional images could not be accurately reconstituted from the glass by projection, because the human eye cannot reproduce the optical distortions induced by the condensing and objective lens systems used in most projectors. This is due in large part to the fact that the human eye generally cannot perceive depth or perspective in projected images.
In recent times, artists have nevertheless used projection in an effort to recreate three dimensional images. Attempts have been made, for example, to use two distinct but overlapping image projections of polarized light to create an illusion of depth. In these circumstances, special three-dimensional viewing glasses are worn for viewing the polarized image projections. These viewing glasses filter the polarized light to present one of the image projections to each eye. The discrepancies between these image projections create the impression of depth in the image.
Other approaches, such as holography, present a three-dimensional image through the interference patterns of two distinct projections of coherent light. In these applications, the phase difference between the light projections is varied such that some points in three-dimensional space appear brighter than others because of the superposition of the crests of the light waves.
The foregoing approaches have inherent limitations, however. Holograms, for example, are very limited in color pallet and exhibit uncontrollable color shift with varying viewing angle. The techniques they employ simply are not practical for reproducing a three-dimensional image from a two-dimensional depiction, because the two-dimensional image has to be initially captured and subsequently processed to include a depth component so that a three-dimensional image can be reconstituted.
Attempts have also been made to recreate three dimensional images by projecting a two-dimensional image upon a stationary three-dimensional object or a molded screen. However, these images are very difficult to edit and they cannot be modified in real time. The need for registration and alignment between the projected two-dimensional image and the three-dimensional projection surface affects the utility of these methods. Additionally, the requirement that these three-dimensional images be recorded in advance generally necessitates film preparation, which further contributes to the registration and keystoning difficulties, not to mention focusing problems associated within the desired depth of field.
In yet another system, interactive image modification is provided through a video shopping device that superimposes computer generated apparel upon an image of a human figure which is captured by a video camera. The human figure adorns an orientation identifying feature that can be recognized by image control circuitry which maps the appropriate orientation of the computer stored apparel image onto the figure and which then displays the composite two-dimensional image upon a viewing screen. This method, however, has drawbacks in that it requires a human figure to wear at least one orientation identifying feature, and it does not provide for the projection of vivid and realistic three-dimensional images. A method of projection which can interactively recreate three-dimensional images from two-dimensional depictions without the need for a video camera, advance processing or the adornment of orientation identifying features would therefore be desirable.
Accordingly, there has existed a definite need for an apparatus and method of projection which can recreate three-dimensional images from two-dimensional depictions without advance processing, and which solves the distortion problems inherent in flat image projection. Additionally, there has existed a need for such an apparatus and method that would allow for interactive image modification, and would therefore have applications in a wide range of fields, including by way of example, a guest-interactive amusement attraction, optical engineering, video shopping and cosmetic surgery. The present invention satisfies these needs and provides further related advantages.